It is oftentimes desirable to apply agricultural chemicals to crops so as to stimulate crop growth, control pests, alleviate crop disease or the like. However, since agricultural chemicals are not universally effective for all desired purposes, it is typically necessary for individual chemicals to be applied separately to crop fields. Such a multiple application technique, of course, increases the time needed in order to apply the individual chemicals to the crop fields and/or requires dedicated multiple application equipment to apply the chemicals simultaneously. As a direct result, therefore, application efficiency of the agricultural chemicals is diminished, while the cost associated with application is increased.
Premixing of the agricultural chemicals in desired ratios so that a single application pass over the crop field is an attractive alternative to the above-described multiple pass application technique. However, there are several real and nontrivial problems associated with premixing of agricultural chemicals. For example, many agricultural chemicals are not shelf-stable when mixed with one another. As a practical matter, therefore, such mixture instability precludes an agricultural chemical manufacturer from supplying end users with dissimilar agricultural chemicals premixed to desired application ratios.
Furthermore, the premixed agricultural chemicals would be subject to government registration procedures requiring, for example, user toxicological and product chemistry studies to be conducted prior to actual use even though each of the agricultural chemicals in the mixture have individually been registered. An exception under the government registration procedures exists, however, if the premixed agricultural chemicals can be supplied to their point of use and transferred to the crop applicator equipment without exposure to the user. Thus, even if it is assumed for the moment that the agricultural chemicals are storage-stable in the mixture, there is currently no known commercially viable means whereby the premixed agricultural chemicals can be stored and transferred to crop applicator equipment via a "closed" system--i.e., a system which precludes exposure of the user to the premixed chemicals during the storage and transfer procedures.
What has been needed, therefore, is a system whereby functionally and/or chemically dissimilar agricultural chemicals may be stored separately of one another in a self-contained tank, yet mixed in a desired ratio prior to crop application. It would furthermore be highly desirable if such a system could transfer the mixture of agricultural chemicals to crop applicator equipment without exposure to the end-user (i.e., so that the self-contained storage and mixing tank could qualify as a "closed" system for purposes of government regulatory rules). It is towards fulfilling such needs that the present invention is directed.
Broadly, the present invention is embodied in a self-contained pressurized and portable tank system whereby dissimilar agricultural chemicals can be stored separately of one another, yet are mixed at a selected ratio in response to transferal of the chemicals to crop applicator equipment. More specifically, the present invention is embodied in a portable holding and mixing tank system for liquid chemicals which includes a tank having at least two fluid-isolated holding compartments (e.g., separate tank units or a dividing wall within the tank interior space) for holding a respective one of the dissimilar liquid chemicals.
A manifold assembly defines respective channels for the liquid chemicals and for pressurizing fluid supplied from a source thereof. The liquid and pressurizing fluid channels are fluid-connected to each of the holding compartments. A pressurizing supply conduit fluid-connects the source of pressurizing fluid to the pressurizing fluid channel, while liquid supply risers respectively fluid-connect the liquid chemicals contained in each of the holding compartments to the liquid channel defined by the manifold assembly. A liquid discharge port fluid-connects the liquid channel defined by the manifold assembly.
As a result, the liquid chemicals within each of the holding compartments are forcibly introduced by means of the pressurizing fluid therewithin into the liquid channel defined by the manifold assembly and are mixed with one another within the liquid channel prior to discharge through the discharge port.
These, as well as other, aspects and advantages of the present invention will become more clear after careful consideration is given to the detailed description of the preferred exemplary embodiment thereof which follows.